1. Technical Field:
This invention relates to machine tools and more particularly to an inexpensive precision linear position indicator system.
2. Background Art
Linear position indicating devices are necessary for providing the feedback signals required to synchronize the absolute position of X-Y positioning tables or other mechanical positioners to their associated electronic controls. One type of position indicators are linear resolvers such as scales supplied by Farrand or Sony. A second type of indicator uses angular resolvers or encoders that more easily interface with microprocessor type controls. In smaller positioning devices, it is customary to mount the feedback device directly to the motor drive. The drive motor in turn positions the X-Y table via a precision rack and pinion or lead screw drive. On larger tables with increasing table size and weight this approach becomes increasingly expensive and impractical and it is customary to separate the drive from the linear position feedback device.